NOTICE Bicron reserves the right to make changes to any product to improve reliability, function or design and does not assume any liability arising from either application or use of any product or circuit described herein. Information presented in this publication has been carefully checked and is believed to be entirely reliable; however, no responsibility is assumed for inaccuracies. Furthermore, the information does not convey to the user any license under the patent rights of Bicron or others. Specifications subject to change without notice.

LIMITED RIGHTS LEGEND The data in this manual is considered &quot;proprietary data.&quot; It may be duplicated and used by or on behalf of the customer with the express limitations the &quot;proprietary data&quot; may not be disclosed outside the customer or be used for purposes of manufacture without prior permission of the seller. This legend shall be marked on any reproduction of this data in whole or in part.

Surveyor M Portable Count-Rate Meter 1064-0-U-0594 User's Manual FOREWORD This manual provides the basic installation, operation, and maintenance procedures for the Bicron Surveyor M Portable Count-Rate Meter. Section 1.0 Introduction provides a general description of the instrument and its operation, and a detailed listing of its physical and performance specifications. Section 2.0 Battery Installation describes the procedure for changing the battery and checking its performance. Section 3.0 Setup describes the settings for the GM Probe and the Scintillation Probe, and how to set the High Voltage. Section 4.0 Operation provides a detailed description of all the features, settings, and complete operating instructions for the Surveyor M. Section 5.0 Circuit Description provides a brief description of the three electronic circuits that make up the instrument. Section 6.0 Calibration provides directions for calibration of the instrument. The Appendices are: A) QC Acceptance Procedure which includes calibration procedures, B) a complete spare parts list so instruments can be repaired on-site, and C) schematic and pictorial diagrams to facilitate repair procedures. Page 1

STANDARD WARRANTY Instruments and options manufactured by Bicron are warranted against defects in materials and workmanship for a period of two years from the date of shipment, unless otherwise agreed upon by Bicron and the customer. Bicron's obligation with regard to such products shall be limited to repair or replacement, FOB Bicron factory or authorized repair station, at Bicron's option. The calibration (when applicable) for each instrument is warranted to be within its specified accuracy at the time of shipment. If this initial calibration is determined to be in error, the instrument will be recalibrated at no charge, provided it is returned as described above.

EXCLUSION OF WARRANTY The aforesaid warranty does not cover instruments, options or probes that are subject to excessive physical abuse or are used for purposes other than those intended. In no event shall Bicron be liable for consequential or special damages, transportation, installation, adjustment, work done by the customer or other expenses that may arise in connection with such defective product or parts. There are no warranties, express or implied, including without limitation any implied warranty of merchantability or fitness, which extend beyond the description of the face hereof. This express warranty excludes coverage of and does not provide relief for incidental or consequential damages of any kind or nature, including, but not limited to loss of use, loss of sales, or inconvenience. The exclusive remedy of the purchaser is limited to repair, recalibration, or replacement of the instrument at Bicron's option. This warranty specifically excludes the following items which are covered by their original manufactures' warranties: photomultiplier tubes, GM and proportional tubes, crystal and other solid-state detectors, and batteries.

Surveyor M Portable Count-Rate Meter Page 6 User's Manual PROCEDURES and CAUTIONS The equipment herein described is designed and manufactured in compliance with all applicable safety standards. Nevertheless, certain hazards are inherent in the use of electronic and radiometric equipment. Adequate warnings are included in the manual and on the product itself to cover hazards that may be encountered in normal use and servicing of this equipment. No other procedures are warranted by Bicron. It shall be the owner's or user's responsibility to ensure that the procedures and cautionary notes are heeded. Failure on the part of the user in any way to follow the prescribed procedures shall absolve Bicron and its agents from any resulting liability. This instrument is intended solely for the detection and measurement of ionizing radiation. It should be used only by persons who have been trained in the proper interpretation of its readings and the appropriate safety procedures that should be followed in the presence of radiation. All instructions and warnings contained in this manual or on the instrument must be read before use and must be strictly followed. Failure to follow these instructions and warnings may result in inaccurate readings and/or user hazard. Indicated battery and other operations tests must be performed prior to each use to assure that the instrument is functioning properly. 1064-0-U-0594

CAUTION FAILURE TO CONDUCT PERIODIC PERFORMANCE TESTS IN ACCORDANCE WITH ANSI N323-1978, PARAGRAPHS 4.6 AND 5.4, AND TO KEEP RECORDS THEREOF IN ACCORDANCE WITH PARAGRAPH 4.5 OF THE SAME STANDARD, COULD RESULT IN ERRONEOUS READING OF POTENTIAL DANGER. ANSI N323-1978 BECOMES, BY THIS REFERENCE, A PART OF THIS OPERATING PROCEDURE.

INSPECTION Instruments should be examined and tested as soon as received. Claims for transportation damages, if any, should be filed at once with the delivery carrier.

Surveyor M Portable Count-Rate Meter 1064-0-U-0594 User's Manual 2.0 Battery Installation The Surveyor M is delivered with a 9-volt Mallory MN 1604 battery, or equivalent. This section defines the procedures for replacement and testing of the battery. Note that some instruments have a parallelwired battery option. In this case, two batteries are wired into the circuit. Installing a second battery thus provides twice the operational hours. Only one battery is needed to power the instrument, however. 2.1 Procedure 1. Turn the instrument off. 2. Open pull catches at both ends of the case and separate the bottom of the case from the top. Install the battery in the appropriate clip on the bottom circuit board, observing proper polarity. The spare battery clip is appropriately marked. Replace the bottom part of the case, orienting the rubber pad under the battery; close the catches. 2.2 Battery Test Turn the control switch (Figure 1) to the &quot;bat.&quot; position; the meter should display a reading within the &quot;bat. ok&quot; checkband. 2.3 High Voltage Measurement Turn the control switch (Figure 1) to the &quot;HV&quot; position. Detector high voltage is directly displayed on the lower meter scale. Page 9

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Surveyor M Portable Count-Rate Meter Page 10 User's Manual 3.0 Setup Both GM and scintillation probes can be used with the Surveyor M. The choice of probe determines which setup procedure should be followed. 3.1 GM Probes The setup for GM probes requires that the high voltage be set (usually to 900V) before the probe is connected to the instrument. See Section 3.3 High Voltage Adjustment for procedural details. Recommended internal switch settings are shown in Table 1. Refer to Figure 3 for the location of the switches. CAUTION Do not use the X1000 range with GM probes. Erroneous readings may result. Do not exceed the GM probe's maximum high voltage rating. 3.2 Scintillation Probes The setup for scintillation probes requires that the high voltage appropriate to the application first be determined. To determine this high voltage setting: 1. 2. Turn the response switch to &quot;fast&quot;. Place a small reference source of the type to be measured near the window of the probe, in a fixed geometry. Set the high voltage to zero. (See Section 3.3 High Voltage Adjustment.) With the instrument on one of its counting ranges, slowly increase the high voltage setting until counting begins. Switch to high voltage and note the voltage. Increase the high voltage by 100 volts. Switch to an appropriate counting range and note the counting rate.

GM Probe Setting either ON ON either Scintillator Probe Setting either ON OFF either

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Switch ID SW3 SW6 SW7

Name Full Scale Alarm Deadtime Compensation Anti-saturation Audio

Factory Setting ON ON (Turn OFF for calibration) ON OFF

Table 1 Internal Switch Settings

Surveyor M Portable Count-Rate Meter 1064-0-U-0594 User's Manual 3.0 Setup (cont'd) 3.2 Scintillation Probes (cont'd) 8. Repeat Steps 5, 6, and 7 until you find a region where the counting rate remains relatively constant when the high voltage is varied by +50 volts (counting rate plateau). Once this plateau has been found, record the counting rate and the high voltage setting for future reference. CAUTION Do not exceed the scintillation probe's maximum high voltage rating. Recommended internal switch settings are shown in Table 1. Refer to Figure 3 for the location of the switches. 3.3 High Voltage Adjustment This control is located on the front panel for easy adjustment of the detector high voltage. The actual high voltage setting is read on the meter scale when the selector switch is in the &quot;HV&quot; position (Figure 1). Clockwise rotation of this control increases the high voltage, while counterclockwise rotation decreases it. Note that it may take a few seconds for the voltage to decrease following a counterclockwise adjustment. The normal factory high voltage setting is 900V. CAUTION A high voltage setting higher than the maximum high voltage specified for the probe being used may cause damage to the probe! Page 11

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Surveyor M Portable Count-Rate Meter Page 12 User's Manual 4.0 Operation 4.1 Radiation Measurement 1. Determine which type probe you will be using. Check the high voltage setting (Section 2.3 High Voltage Measurement) and connect the probe. Set the appropriate external controls: audio, response, and counting range settings. See Section 4.2 External Controls for details. Set the internal switches to the appropriate settings for your operation. See Section 4.3 Internal Controls for details. Perform the survey, making sure to multiply the meter reading by the counting range setting to obtain the reading in counts per minute. Note: When using GM probes, select only the X1, X10, or X100 counting ranges; do not use the X1000 range. Any of the four ranges may be selected when using scintillation probes. 6. 2. If your meter is equipped with the optional Digital Scaler, press the Count Button on top of the case to activate the digital scaler. The Count Light will illuminate, indicating that a count is in progress. When the light turns off, the count time has been completed. Once a count is started, the Count Pushbutton is electronically locked out to prevent accidental restarting. If you wish to reset the scaler during a count, turn the instrument off for a few seconds, then turn it back on and press the Count Pushbutton again. 1064-0-U-0594

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Surveyor M Portable Count-Rate Meter 1064-0-U-0594 User's Manual 4.0 Operation (cont'd) 4.2 External Controls All the external controls are located on the top of the instrument (Figure 1). Audio The Surveyor M is equipped with an internal speaker that will produce an audible click for each detector pulse. This speaker is controlled by a panel-mounted ON/OFF switch labeled &quot;audio&quot;. If the Audio Switch is in the OFF position, an audible &quot;over-range&quot; alarm will sound when the meter is approximately 30% or more above full scale on any range. When the Audio Switch is in the ON position, the Over-range Alarm in not operational. The Over-range Alarm also can be disabled by turning the Internal Alarm Switch (SW3) OFF. See Section 4.3 Internal Controls for details. Response Time In addition to the built-in circuitry that optimizes response time for each range, a front panel switch labeled &quot;response&quot;, with position &quot;fast&quot; and &quot;slow&quot; may be used to tailor response time to the survey situation. Mode/Range Selector This seven position knob selects the operating mode and the counts per minute scaling when used in survey mode. The off setting turns off all power to the unit. The bat. position tests the voltage of the battery; it should read in the &quot;bat. ok&quot; range of the meter. The HV setting displays the output of the high voltage circuit in kilovolts. The X1000, X100, X10, and X1 settings are various scale ranges to be selected based on the radiation being surveyed. Note that the X1000 range should be used only with the Scintillator Probe. Digital Scaler For those units equipped with a Digital Scaler, the top mounted totalizer has six digits available for displaying the total count. The Count pushbutton is used to initiate a count; the light indicates when a count is in progress. Page 13

Surveyor M Portable Count-Rate Meter Page 14 User's Manual 4.0 Operation (cont'd) 4.3 Internal Controls Three internal switches are included with the basic Surveyor M to allow user customization of some of the instrument's features. If the Scaler Option is installed, a fourth internal switch is included. Full Scale Alarm Switch This ON/OFF switch is SW3 on Figure 3. When this switch is in the ON position, the full-scale alarm circuit is enabled, and will sound only when the Audio Switch is OFF and the count rate exceeds the upper end of the meter's range by 30%. To disable the Full-scale Alarm, turn this switch OFF. The factory setting of this switch is ON. Anti-saturation Switch This ON/OFF switch is SW7 on Figure 3. When this switch in ON, the anti-saturation circuitry is enabled. This circuit is used to prevent over-range foldback of GM probes due to GM tube saturation. With Bicron EWGM and SWGM probes, over-range foldback is prevented in fields typically up to 1000R/h; for the Bicron PGM, it is prevented in fields typically up to 5R/h. The Anti-saturation Switch must be turned OFF whenever a Scintillation Probe is used; otherwise, the voltage divider in the probe may engage the anti-saturation circuitry erroneously. The factory setting of this switch is ON. 1064-0-U-0594

Figure 3 Main Circuit Board Assembly

Surveyor M Portable Count-Rate Meter 1064-0-U-0594 User's Manual 4.0 Operation (cont'd) 4.3 Internal Controls (cont'd) Dead-time Compensation Switch This ON/OFF switch is SW6 on Figure 3. When this switch is ON, the dead-time compensation circuit is enabled. This circuit provides dead-time loss correction for both GM and scintillation probes. Note: This switch will affect the frequencies used to calibrate the instrument on the four count-rate ranges due to the effect of the dead-time correction circuit on the analog meter reading. Typically, calibration will be performed with this switch OFF. Refer to the Q.C. Acceptance Procedure (Appendix A) for more information. The factory setting of this switch is ON. Digital Scaler Count Time Switch This three position switch (SW102 on Figure 3) controls the length of time during which the counts are totaled when using the Digital Scaler Option. The available times are 0.1, 1, and 10 minutes, as indicated on the circuit board. Be sure the instrument is turned OFF when changing the position of this switch. The normal factory setting for this switch is one minute. 5.0 Circuit Description The electronic circuitry in the Bicron Surveyor M with Digital Scaler Option is contained on four interconnected printed circuit boards. Modern solid-state integrated circuitry is used throughout. The major components are the following: 1. High-voltage power supply. This is a feedback-regulated, electronically stabilized supply for the detector potential. Additional circuitry provides high voltage readout on the meter scale. Count-rate meter. A linear charge pump ratemeter converts the detector pulses to a count rate reading on the calibrated meter scale. The circuitry includes a unique resolving time compensation technique to provide linear response over the full range with both scintillation and GM probes, automatic and manual time constant selection, and temperature compensation. Audio circuitry. This circuit provides for individual pulse counting and the Overrange Alarm. Digital scaler circuitry. Page 15

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6.0 Calibration The SURVEYOR M, being a count-rate instrument, is normally calibrated electronically in counts per minute. Detailed calibration procedures are part of the Q.C. Acceptance Procedure found in Appendix A.

Note: See Figure 3 for the location of all Circuit Board components not labeled on the board. 2. Remove the 9V battery and connect a 9.30V+.05V power source across the battery terminals on the battery board. Perform the following adjustments: 4. a. Turn the control switch OFF. Mechanically zero the meter via the rear adjustment screw on the meter barrel. Turn the control switch to X1000. Check the +5V supply at Pin 1 of U6 (ICL 7663). The reading should be 5VDC +0.5 V. Leave the control switch set at X1000 and connect a voltmeter between pins 1 (ground) and 15 of the 24-pin connector. Adjust R31 (50 kohm zero pot, &quot;ZERO&quot;) until the voltmeter reads 1 mVDC +2 1/2, -1 mVDC. Check the voltage reading on the X100, X10, and X1 ranges. Little change should occur. Turn the control switch to &quot;HV&quot; and connect a high voltage measuring device with an impedance greater than 1000 megohms to the probe connector center pin. Adjust the high voltage supply to +1000 VDC

3.

Perform a CPM Calibration. a. Turn ON SW6 (dead-time compensation), turn OFF SW7 (antisaturation). Connect a variable frequency pulse generator (amplitude of -1.5 v, pulse width of 10 microseconds) between Pin 5 and Pin 1 of the 24-pin connector header. Adjust the frequency of the pulse generator to the value listed in Table T1 required to calibrate the unit at 80% of full scale on the meter. Adjust R21 (the 5 Kohm calibration pot, X1000) until the meter reads 80% of full scale. Readjust the frequency of the pulse generator to the value listed in Table 1 required to calibrate at 20% of full scale.

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Surveyor M Portable Count-Rate Meter Page 18 User's Manual Appendix A (cont'd) f. Note the meter readings from steps 4d and 4e on a Certificate of Calibration. Repeat Steps 4c through 4f for the X100 range using R19 (the 50 Kohm, X100 calibration pot). Repeat Steps 4c through 4f for the X10 range using R17 (the 500 Kohm, X10 calibration pot). Repeat Steps 4c through 4f for the X1 range using R15 (the 5 megohm, X1 pot). Turn SW6 OFF. Check the above four-range calibration, except using Table T-2 for the calibration frequencies. No adjustment to any of the four potentiometers should be required; this is a test of the linearity of the circuit without dead-time compensation. Leave the pulse generator connected when calibration is complete. Mark all trimpot bodies to show the general position of the adjustment screws after calibration. c. 7. b. 6. Test the audio as follows: a. Turn the Audio Switch ON and check to see that the audio functions properly on all four counting ranges, using the pulse generator. Also, check that the audio remains silent when the selector switch is on &quot;bat.&quot; and &quot;HV&quot;. Turn the Audio Switch OFF and SW3 (alarm ON/OFF switch) on the main PC board to ON. Drive the meter well beyond full scale with the pulse generator and observe that a continuous tone is heard. Do this on all four counting ranges. Disconnect the pulse generator. 1064-0-U-0594

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Turn the control switch to &quot;HV&quot; and adjust the high voltage to +900 VDC via the front panel control. Test the antisaturation circuit as follows: a. Turn the control switch to the &quot;X1000&quot; position and connect a 500 megohm resistor across the probe connector (from +900V to ground). The meter should peg beyond full scale. Replace the 500 megohm resister with a 2000 megohm resistor. The meter should remain at zero. Remove the 2000 megohm resistor and reinstall the 500 megohm resistor.

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Turn the response switch to &quot;fast&quot; and the control switch to &quot;X1000&quot;. Vary the frequency of the pulse generator to obtain a reading near full scale and switch between &quot;fast&quot; and &quot;slow&quot; to check the operation of the response switch. Do the same for the X100, X10, and X1 ranges. Leave the pulse generator connected.

8.

Remove all test equipment. Turn the instrument OFF and install a new 9 volt battery in the appropriate battery holder. (Either holder may be used if the holders are parallel-wired.)

Surveyor M Portable Count-Rate Meter 1064-0-U-0594 User's Manual Appendix A (cont'd) 9. Attach a probe to the instrument, observing the proper high voltage precautions. Place the probe near an appropriate check source and turn the selector switch to each of the four ranges in turn. A meter reading should be obtained for each range. &quot;count&quot; pushbutton. Time the count period; it should be 0.1 minutes. c. Set the digital scaler for a 1 minute count time. Turn the control switch to one of the four counting ranges and press the &quot;count&quot; pushbutton. Time the count period; it should be 1.0 minutes. Compare the CPM reading on the analog meter to the digital scaler total count; they should be the same. Page 19

10. If the instrument is equipped with the Digital Scaler Option, perform the following tests: a. Connect a frequency counter to pin 11 of U101 (4011 IC). The frequency should be 32.768 kHz + 0.1%. Set the digital scaler for a 0.1 minute count time. Turn the control switch to one of the four counting ranges and press the

11. Turn the instrument OFF and disconnect the probe. Make sure that the internal switches are set as follows: SW3 (alarm) ON, SW6 (dead-time compensation) ON, and SW7 (anti-saturation) ON. 12. Complete, date, and sign a Certificate of Calibration.